This invention relates to apparatus and method for combusting crude oil and, more particularly, relates to apparatus and method for combusting crude oil during oil well production tests.
The development and improvement of apparatus and methods for abating any pollution created during oil and gas exploration and production are a high priority for the industry. One source of such pollution is the hydrocarbon fluids produced during the well production tests which are conducted to provide an estimate of the maximum flow and composition of the fluids to be produced from a well. There are a number of uncertainties which create pollution-related problems during production tests. For example, some of the production tests are conducted after the well is drilled and before facilities are built to handle the produced fluids, since one purpose of the tests is to determine the type and capacity of equipment needed to process the produced fluids so that the fluids may be transported or stored. Once a production test is started, it must be allowed to continue for a known period of time to accurately predict the production capacity of a well; and, therefore, the disposal system must be able to accommodate the unknown, widely-fluctuating flow rates and unknown composition of the produced fluids. The oil produced during a well test often contains gas, contaminants, and particulate matter and is therefore difficult to store, transport, or burn, particularly on offshore platforms and in remote locations.
Because of these uncertainties, the current practice of the industry is to burn the produced fluids (hereinafter referred to as "crude oil"). To the best of applicant's knowledge, the crude oil produced during well tests has always been burned using open-air burners, i.e., flares in which the burner and flame are exposed to the open air. For examples see U.S. Pat. Nos. 3,565,562; 3,632,287; 3,797,992; 3,807,932; 3,914,094; 3,948,196; 3,980,416; 4,348,171; 4,412,811; and 4,452,583. These open-air burners are difficult to control and often produce large volumes of black smoke, volatile organic compounds, unburned hydrocarbons, carbon monoxide, nitrogen oxides, and unburned oil which is deposited on the land or water around the burner. This is attested to by some of the prior patents which disclose apparatus for reducing the smoke created during open-air burning.
Despite prior attempts to provide an environmentally acceptable open-air burner, none have proven entirely satisfactory. The present invention provides method and apparatus for burning the crude oil, as well as other hydrocarbon products, produced during a well test in a pollution abating, environmentally acceptable manner by enclosing a burner or nozzle and controlling the combustion of the crude oil so that a virtually pollution-free combustion is achieved. Although burners for commercial quality oil which enclose the flame are known, such as those disclosed in U.S. Pat. No. 2,701,608 and U.S. Pat. No. 3,603,711; as are burners for contaminated oil which partially enclose the flame to reduce noise levels during burning, as disclosed in U.S. Pat. No. 4,155,702; in the applicant's knowledge no attempt has been made to totally enclose the combustion of crude oil produced during well testing. Further, no attempt has been made to use the heat of combustion of the crude oil to enhance the combustion and produce a pollution abating combustion. It is contemplated that the wide range of flow rates and the unpredictable qualities of the crude oil encountered during well testing, as well as the extreme temperatures and the concern with keeping the size and cost of the disposal facilities at a minimum, have taught away from enclosing the combustion of crude oil produced during well tests.